The present invention relates generally to a light that turn on in response to a signal from a detector, and more particularly to movable or portable motion-sensing lights that can be plugged into a standard electrical outlet.
Motion-sensing lights are used in a variety of ways to increase the safety, security, and convenience of one's home. A porch light that automatically comes on when someone approaches the porch, or a floodlight that automatically comes on when someone is in the driveway are examples of uses of these types of lights. These types of light often use a passive infra-red (“PIR”) detector to sense motion of an object, turn on the light for a pre-selected period of time, and then turn the light off. Often, the lights are also provided with a photo-detector to prevent the light from turning on in daylight. Many such lights have adjustable sensitivity, and an override switch for testing or standard switched operation.
Unfortunately, such lamps are permanently wired into a standard 4-inch octagonal electrical box. The lamp is often sold with the mounting hardware, including a gasket to seal the lamp, if the lamp is to be used outdoors. The gasket is typically a thin piece of rubber or foam rubber, and the mounted light might leak if the gasket is not properly aligned when it is installed; however, the standard electrical boxes typically have punch-outs for wire entries that can leak water. Therefore, the boxes are intended to be installed inside or behind a wall. Similarly, if a utility box is not already where the light is desired, the wiring and box must be installed. Even hooking up the lamp to existing wiring might be more than a homeowner might want to attempt, and professional assistance is often hired, adding to the cost of installing such a light.
Some motion-sensing lights use batteries to power the lamps and the sensing circuit. Unfortunately, batteries run out of power eventually, and the light may fail unless the batteries are replaced in time. This can add to the cost of operation and unreliable operation. Similarly, a compromise is often made between the light output and draw on the battery power.